Flame protector for gas burners



Oct. 4, 1966 A. B. FREDHOLD, JR., ETAL 3,276,509

FLAME PROTECTOR FOR GAS BURNERS Filed MaFCh 50, 1964 United StatesPatent O 3,276,509 FLAME PROTECTOR FR GAS BURNERS Allan B. Fredhold,Jr., San Marino, and Robert E. Wilkinson, La Mirada, Calif., assignorsto Interstate Engineering Corporation, Anaheim, Calif., a corporation ofCalifornia Filed Mar. 30, 1964, Ser. No. 355,858 1 Claim. (Cl. 158-113)This invention relates to a ame protector or flame retention ring forgas burners and particularly to a type of gas burner used in thelconstruction of gas refrigerators used in house trailers, campers, andthe like.

Explanatory for the present invention, house trailers, campers, and thelike now frequently employ gas refrigerators which are operated by a gasburner having a relatively low stand-by flame. Such a burner is usuallylocated vertically beneath and in spaced relation to the lower end of avertical llue tube around which there may be arranged a heat exchangecoil containing the lluids of the gas refrigerator. The llue tube andthe 'burner structures as applied to this invention are usually locatednear an outside wall of the house trailer or camper and louvered ventsare usually arranged near the bottom of the liue tube and near the topof the ue tube in the -outside wall. The lower louvered vent is usuallyrelied upon to permit ingress of air to .supply the oxygen forcombustion of the gas issuing from the burner, and the upper louveredvent is usually relied upon to permit the products of combustion afterthey have risen to the flue tube to escape through the outside wall ofthe trailer to the exterior thereof. The burner conventionally employedfor this purpose is a small cylindrical burner having a top in whichthere is usually an annular row of perforations. There may or may not becentral perforations in the top of the burner.

It has been found that frequently the flame of the burner which isusually small becomes blown out and extinguished. This tnay occur Ias aresult of either of two different circumstances. A strong wind blowingagainst the exterior of the trailer or camper and through the lower ventmay blow across the top of the burner with sucient force to blow out thellame and cause the flame to be extinguished. The other circumstance maybe occasioned when the trailer or camper is moving in one directionyalong a road or highway and passes a truck or vehicle that is movingalong the highway in the opposite direction. Under these conditions,there may be a sudden puits of air through the upper vent which iscaused to pass suddenly down through the flue tube. This pull `which isdirected by the flue tube down against the top of the burner spreads thellame of the burner and extinguishes it.

A primary object of the present invention is to provide a shield orllame retention ring which can be easily and quickly applied to theburner and which will protect the flame of the burner from beingextinguished in the event of either of the :above `mentionedcontingencies.

With the foregoing and other objects in view which will become manifestin the following detailed description and specically pointed out in theappended claim, reference is had to the accompanying drawings for anillustrative embodiment of the invention, wherein:

FIGURE l is a partial view in vertical section through a portion of anexterior wall of a house trailer or camper showing the refrigeratoradjacent thereto and its burner supplied with the llame retention ringembodying the present invention.

FIGURE 2 is a view of the burner taken substantially upon the line 2-2upon FIGURE 1 in the direction indicated.

FIGURE 3 is a partial view largely in section taken substantially uponthe line 3-3 upon FIGURE 2.

Referring to the accompanying drawings wherein similar referencecharacters designate `similar parts throughout, 10 indicates an exteriorwall of a house trailer or camper adjacent which there is installed agas refrigerator generally indicated 'at 11. The details of constructionof the gas refrigerator 11 are variable and are immaterial except forenvironmental use of the burner and protector in so far as the presentinvention is concerned. However, most constructions of this type have avertical flue tube 12 that is located at the back of the refrigeratoradjacent the exterior wall 10 and beneath which there is a gas burnergenerally indicated at 13, that is supplied with gaseous fluid through aconduit 14 from a tank or other source of supply (not shown). The lowerend of the llue tube 12 is disposed near a lower vent 15 in the wall 10that is normally covered by louvers 16. The upper end of the flue tube12 is disposed adjacent an upper vent 17 in the wall 10 which islikewise normally covered by louvers 18. The burner 13 is of generallycylindrical shape having in its top an annular row of perforations 19.There may or may not be in addition to these perforations centralperforations 20. A typical burner used for this purpose is a Teddingtontype TZ, although the invention is applicable to other types of burnershaving the same general construction or conliguration.

As previously stated, a strong wind blowing laterally against theexterior wall 10 -and through the lower vent 15 can sweep across the topof the burner and blow out and extinguish all of the flames issuing fromthe perforations 19 and the perforations 20, if the latter perforationsexist. Also, in the course of travel, if the trailer or camper passes atruck or other large vehicle that is moving in the opposite direction, amomentary puff of :air sometimes enters the upper vent 17 and passesdown through the llute tube 12 against the top of the burner 13. In thelatter event, the flames issuing from the perforations 19 are caused tospread radially and the flame to be extinguished. The blowing out of theflames in either contingency is `rather easily accomplished,particularly when the flame is small as is the case when only a stand-byllame is being employed.

The device embodying the invention consists of a concavo-convex ring 21that may be stamped from sheet metal or otherwise constructed. This ringmay be frustoconical in shape, as shown, or may be in the form of asection of spherical shape. It rests at its innerl and lower edge on thetop of the burner 13 and extends upwardly and outwardly terminating inan outer annular edge 22, which is disposed adjacent .but not directlyover the perforations 19. This edge 22 should be suliiciently close tothe llow issuing from the perforations 19 so that the ring will beheated `thereby and avoid the deposit of carbon thereon. The ring isheld centrally on the burner, such as by three integral attaching 'arms23, which extend from the edge 22 outwardly and downwardly, thendownwardly along the sides of the burner, and nally inwardly .as at 24beneath the burner.

In the event that wind blows against the wall 10 and through the lowervent 15 across the top of the burner, flames issuing from thoseperforations 19 that are closest to the vent or which are between thellame retention ring 21 and the vent 15 may actually be blown out.However, those flames which are on the opposite side of the retentionring from the vent 15 are effectively protected by the retention ringfrom being extinguished. Consequently, `when the draft through the vent15 is relieved, these llames that have been thus protected by theretention ring will re-ignite the gas jets issuing from the perforations19 most adjacent the lower vent 1S.

In the event that -a puff of air is caused to enter the upper vent 17and blow downwardly through the flue tube 12, this .air encounters theconcave upper face of the ring 21. The upwardly and -outwardly inclinedring effectively protects the flames issuing from lthe perfora-`tions'19 from being blown out by this reversed flow of air downwardlythrough the flue tube 12.

Where the burner is not equipped with the central perforations 20, the`center of the ring 21 need not be left open, as shown, and the shieldunder these circumstances may be in the nature of a concavo-convex discthat is held on the top of the burner such as by the securing arms 23.

It will be appreciated from the above described construction that theflame protector embodying the present invention is of very simple anddurable construction and will effectively prevent the burner from havingits llame blown out under circumstances that commonly cause the flame tobe extinguished in burners of this type. It has been our observationthat in many instances the combustion of the burner is improved by thepresence of the flame protector and that the carbon monoxide content ofthe products of combustion is materially reduced. This improvement maybe caused by the increased air turbulence or air mixing created by thepresence of the ring 21 in the immediate 'vicinity of the perforations19. Combustion improvement is not invariably obtained, but is noticeablein certain instances depending upon the size of the ame and otherphysical conditions of the systems.

Various changes may be made within the scope of the present invention,as dened by the appended claims.

We claim:

In `combination with a gaseous fuel burner having annularly arrangedfuel orifice means disposed beneath and in spaced relation to a fluetube surrounded by a refrigeration me-ans which in turn has its top andbottom disposed adjacent to air supply and combustion air vents in anouter contiguous wall, a flame protector from down drafts and crossdrafts 'comprising a -concaVo-convex arcuate shield disposed on top ofthe burner with a lower portion contacting the top of the burnerinwardly of said annularly arranged orifice means and having Aa higheroutward portion in upwardly sloping spaced relation to the top of theburner and lying closely adjacent to but inwardly yconcentric from saidorice means and arranged to be heated by the llame therefrom to preventdeposit of carbon thereon, and straps secured to the upper rim of theflame protector, said stuaps subtending the lower end of the `burnerbody whereby the llame protector is secured to the burner unit.

References Cited by the Examiner UNITED STATES PATENTS 601,426 3/1898Buerkle 158-99 1,397,160 11/1921 Campbell. 1,949,026 2/1934 Nitka126-307 2,220,247 11/1940 Kochendorfer et al. 158-113 X 2,225,20312/1940 Barnes 126-56 X 2,303,807 12/1942 Wilson 158-131 X 2,372,9534/1945 Hurlbut et al. 158-116 2,518,329 8/1950 Janson et lal 126-562,855,034 10/1958 Iohn 158-115 3,056,450 10/1962 Loveland et al. 158-116X FOREIGN PATENTS 1,047,738 7/ 1953 France.

FREDERICK L. MATTESON, JR., Primary Examiner.

